Ring opening co-polymerization of succinic anhydride derivatives and epoxides from bio-based resources via organocatalysis – CoCaBio

Organic monomer synthesis
Organocatalytic polymerization of monomers.

1) A series of 9 squaramides and 9 corresponding thiosquaramides were synthesized according to methods reported in the literature. A croconamide was also obtained.
2) 4 epoxides were synthesized from eugenol, geraniol and furfural (biosourced product obtained from sugars) via methods described in the literature. These products are obtained in racemic version at the 40 gram scale. The glucose-derived epoxides proposed as targets in our initial project have been synthesized but they are too unstable to be exploited in polymerization. We have also synthesized safrole oxide and we are going to synthesize other epoxides from alcohols of renewable origin not considered in our initial project. The synthesis of enantiomerically pure epoxides is well advanced on a small scale (of the order of 100 mg): we will try to obtain them on a gram scale, which is the minimum quantity needed to carry out the polymerizations.
3) Enantioselective organocatalyzed Michael reactions between carbon nucleophiles and itaconic anhydride or diethyl fumarate have led to degradation products. This route was abandoned. We have therefore changed the target and obtained 3 succinic anhydride derivatives, on a gram scale, bearing amide functions from aspartic acid, identified by the US Department of Energy in 2004 as one of the 10 value-added products that can be derived from biomass.
4) The synthesized organocatalysts did not give convincing results in copolymerization of succinic or phthalic anhydrides with cyclohexene oxide. On the other hand, we showed that thiosquaramides were more efficient than the corresponding squaramides in another ring-opening polymerization reaction of lactides. We are currently writing a publication on this work.
Engaged in the co-polymerization reaction with phthalic anhydride, the racemic safrole epoxide led for the first time, by organocatalysis with PPNCl, to the corresponding atactic polyester.
5) The characterization of the new materials obtained is currently in progress.


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Other racemic and enantiomerically pure catalysts and epoxides will be tested in this reaction. New enantiomerically pure polyesters could lead to novel materials, especially by combining the products from S-configuration monomers with those from E-configuration monomers.
Succinic anhydrides derived from aspartic acid will also be tested in this reaction, initially in the presence of cyclohexene oxide and then, if successful, with the other synthesized epoxides.

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Organo-catalyzed/initiated ring opening copolymerization of cyclic anhydrides and epoxides: an emerging story Dmytro Ryzhakov,a Gaël Printz,b Béatrice Jacques,b Samir Messaoudi, a Françoise Dumas, a Samuel Dagorne *b and Franck Le Bideau Polym. Chem. 2021, 12, 2932-2946. (10.1039/d1py00020a). hal.archives-ouvertes.fr/hal-03279235
Review on the subject.

Considering the environnemental impact and the future shortage of fossil resources, the development of materials originating from renewable resources has become a global concern. The main purpose of this project is to place organocatalysis at the service of ring opening polymerization (ROP), for the synthesis of polymers based on renewable resources. It is envisioned that the organocatalytic approach, which has not been truly developed up to now, will complement in the short term, and replace in the long term, organometallic catalyzed methods as an eco-friendly metal-free alternative. The present project focuses on the alternating co-polymerization of succinic anhydride derivatives and epoxides derived from renewable resources, via ROP reactions for the production of diverse polyesters. Succinic anhydride and its derivatives were scarcely used in this field of research, particularly with organocatalysts. Their co-polymerizations with epoxides could afford new materials with novel and tunable microstructures properties thanks to a control of polymer backbone structure and stereoregularity.